base.cc revision 4376 
1/*
2 * Copyright (c) 2002-2005 The Regents of The University of Michigan
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions are
7 * met: redistributions of source code must retain the above copyright
8 * notice, this list of conditions and the following disclaimer;
9 * redistributions in binary form must reproduce the above copyright
10 * notice, this list of conditions and the following disclaimer in the
11 * documentation and/or other materials provided with the distribution;
12 * neither the name of the copyright holders nor the names of its
13 * contributors may be used to endorse or promote products derived from
14 * this software without specific prior written permission.
15 *
16 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
17 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
18 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
19 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
20 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
21 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
22 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
23 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
24 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
25 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
26 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27 *
28 * Authors: Steve Reinhardt
29 */
30
31#include "arch/utility.hh"
32#include "arch/faults.hh"
33#include "base/cprintf.hh"
34#include "base/inifile.hh"
35#include "base/loader/symtab.hh"
36#include "base/misc.hh"
37#include "base/pollevent.hh"
38#include "base/range.hh"
39#include "base/stats/events.hh"
40#include "base/trace.hh"
41#include "cpu/base.hh"
42#include "cpu/exetrace.hh"
43#include "cpu/profile.hh"
44#include "cpu/simple/base.hh"
45#include "cpu/simple_thread.hh"
46#include "cpu/smt.hh"
47#include "cpu/static_inst.hh"
48#include "cpu/thread_context.hh"
49#include "mem/packet.hh"
50#include "sim/builder.hh"
51#include "sim/byteswap.hh"
52#include "sim/debug.hh"
53#include "sim/host.hh"
54#include "sim/sim_events.hh"
55#include "sim/sim_object.hh"
56#include "sim/stats.hh"
57#include "sim/system.hh"
58
59#if FULL_SYSTEM
60#include "arch/kernel_stats.hh"
61#include "arch/stacktrace.hh"
62#include "arch/tlb.hh"
63#include "arch/vtophys.hh"
64#include "base/remote_gdb.hh"
65#else // !FULL_SYSTEM
66#include "mem/mem_object.hh"
67#endif // FULL_SYSTEM
68
69using namespace std;
70using namespace TheISA;
71
72BaseSimpleCPU::BaseSimpleCPU(Params *p)
73    : BaseCPU(p), thread(NULL), predecoder(NULL)
74{
75#if FULL_SYSTEM
76    thread = new SimpleThread(this, 0, p->system, p->itb, p->dtb);
77#else
78    thread = new SimpleThread(this, /* thread_num */ 0, p->process,
79            /* asid */ 0);
80#endif // !FULL_SYSTEM
81
82    thread->setStatus(ThreadContext::Suspended);
83
84    tc = thread->getTC();
85
86    numInst = 0;
87    startNumInst = 0;
88    numLoad = 0;
89    startNumLoad = 0;
90    lastIcacheStall = 0;
91    lastDcacheStall = 0;
92
93    threadContexts.push_back(tc);
94}
95
96BaseSimpleCPU::~BaseSimpleCPU()
97{
98}
99
100void
101BaseSimpleCPU::deallocateContext(int thread_num)
102{
103    // for now, these are equivalent
104    suspendContext(thread_num);
105}
106
107
108void
109BaseSimpleCPU::haltContext(int thread_num)
110{
111    // for now, these are equivalent
112    suspendContext(thread_num);
113}
114
115
116void
117BaseSimpleCPU::regStats()
118{
119    using namespace Stats;
120
121    BaseCPU::regStats();
122
123    numInsts
124        .name(name() + ".num_insts")
125        .desc("Number of instructions executed")
126        ;
127
128    numMemRefs
129        .name(name() + ".num_refs")
130        .desc("Number of memory references")
131        ;
132
133    notIdleFraction
134        .name(name() + ".not_idle_fraction")
135        .desc("Percentage of non-idle cycles")
136        ;
137
138    idleFraction
139        .name(name() + ".idle_fraction")
140        .desc("Percentage of idle cycles")
141        ;
142
143    icacheStallCycles
144        .name(name() + ".icache_stall_cycles")
145        .desc("ICache total stall cycles")
146        .prereq(icacheStallCycles)
147        ;
148
149    dcacheStallCycles
150        .name(name() + ".dcache_stall_cycles")
151        .desc("DCache total stall cycles")
152        .prereq(dcacheStallCycles)
153        ;
154
155    icacheRetryCycles
156        .name(name() + ".icache_retry_cycles")
157        .desc("ICache total retry cycles")
158        .prereq(icacheRetryCycles)
159        ;
160
161    dcacheRetryCycles
162        .name(name() + ".dcache_retry_cycles")
163        .desc("DCache total retry cycles")
164        .prereq(dcacheRetryCycles)
165        ;
166
167    idleFraction = constant(1.0) - notIdleFraction;
168}
169
170void
171BaseSimpleCPU::resetStats()
172{
173//    startNumInst = numInst;
174    // notIdleFraction = (_status != Idle);
175}
176
177void
178BaseSimpleCPU::serialize(ostream &os)
179{
180    BaseCPU::serialize(os);
181//    SERIALIZE_SCALAR(inst);
182    nameOut(os, csprintf("%s.xc.0", name()));
183    thread->serialize(os);
184}
185
186void
187BaseSimpleCPU::unserialize(Checkpoint *cp, const string &section)
188{
189    BaseCPU::unserialize(cp, section);
190//    UNSERIALIZE_SCALAR(inst);
191    thread->unserialize(cp, csprintf("%s.xc.0", section));
192}
193
194void
195change_thread_state(int thread_number, int activate, int priority)
196{
197}
198
199Fault
200BaseSimpleCPU::copySrcTranslate(Addr src)
201{
202#if 0
203    static bool no_warn = true;
204    int blk_size = (dcacheInterface) ? dcacheInterface->getBlockSize() : 64;
205    // Only support block sizes of 64 atm.
206    assert(blk_size == 64);
207    int offset = src & (blk_size - 1);
208
209    // Make sure block doesn't span page
210    if (no_warn &&
211        (src & PageMask) != ((src + blk_size) & PageMask) &&
212        (src >> 40) != 0xfffffc) {
213        warn("Copied block source spans pages %x.", src);
214        no_warn = false;
215    }
216
217    memReq->reset(src & ~(blk_size - 1), blk_size);
218
219    // translate to physical address
220    Fault fault = thread->translateDataReadReq(req);
221
222    if (fault == NoFault) {
223        thread->copySrcAddr = src;
224        thread->copySrcPhysAddr = memReq->paddr + offset;
225    } else {
226        assert(!fault->isAlignmentFault());
227
228        thread->copySrcAddr = 0;
229        thread->copySrcPhysAddr = 0;
230    }
231    return fault;
232#else
233    return NoFault;
234#endif
235}
236
237Fault
238BaseSimpleCPU::copy(Addr dest)
239{
240#if 0
241    static bool no_warn = true;
242    int blk_size = (dcacheInterface) ? dcacheInterface->getBlockSize() : 64;
243    // Only support block sizes of 64 atm.
244    assert(blk_size == 64);
245    uint8_t data[blk_size];
246    //assert(thread->copySrcAddr);
247    int offset = dest & (blk_size - 1);
248
249    // Make sure block doesn't span page
250    if (no_warn &&
251        (dest & PageMask) != ((dest + blk_size) & PageMask) &&
252        (dest >> 40) != 0xfffffc) {
253        no_warn = false;
254        warn("Copied block destination spans pages %x. ", dest);
255    }
256
257    memReq->reset(dest & ~(blk_size -1), blk_size);
258    // translate to physical address
259    Fault fault = thread->translateDataWriteReq(req);
260
261    if (fault == NoFault) {
262        Addr dest_addr = memReq->paddr + offset;
263        // Need to read straight from memory since we have more than 8 bytes.
264        memReq->paddr = thread->copySrcPhysAddr;
265        thread->mem->read(memReq, data);
266        memReq->paddr = dest_addr;
267        thread->mem->write(memReq, data);
268        if (dcacheInterface) {
269            memReq->cmd = Copy;
270            memReq->completionEvent = NULL;
271            memReq->paddr = thread->copySrcPhysAddr;
272            memReq->dest = dest_addr;
273            memReq->size = 64;
274            memReq->time = curTick;
275            memReq->flags &= ~INST_READ;
276            dcacheInterface->access(memReq);
277        }
278    }
279    else
280        assert(!fault->isAlignmentFault());
281
282    return fault;
283#else
284    panic("copy not implemented");
285    return NoFault;
286#endif
287}
288
289#if FULL_SYSTEM
290Addr
291BaseSimpleCPU::dbg_vtophys(Addr addr)
292{
293    return vtophys(tc, addr);
294}
295#endif // FULL_SYSTEM
296
297#if FULL_SYSTEM
298void
299BaseSimpleCPU::post_interrupt(int int_num, int index)
300{
301    BaseCPU::post_interrupt(int_num, index);
302
303    if (thread->status() == ThreadContext::Suspended) {
304                DPRINTF(Quiesce,"Suspended Processor awoke\n");
305        thread->activate();
306    }
307}
308#endif // FULL_SYSTEM
309
310void
311BaseSimpleCPU::checkForInterrupts()
312{
313#if FULL_SYSTEM
314    if (check_interrupts(tc)) {
315        Fault interrupt = interrupts.getInterrupt(tc);
316
317        if (interrupt != NoFault) {
318            interrupts.updateIntrInfo(tc);
319            interrupt->invoke(tc);
320        }
321    }
322#endif
323}
324
325
326Fault
327BaseSimpleCPU::setupFetchRequest(Request *req)
328{
329    // set up memory request for instruction fetch
330#if ISA_HAS_DELAY_SLOT
331    DPRINTF(Fetch,"Fetch: PC:%08p NPC:%08p NNPC:%08p\n",thread->readPC(),
332            thread->readNextPC(),thread->readNextNPC());
333#else
334    DPRINTF(Fetch,"Fetch: PC:%08p NPC:%08p",thread->readPC(),
335            thread->readNextPC());
336#endif
337
338    // This will generate a mask which aligns the pc on MachInst size
339    // boundaries. It won't work for non-power-of-two sized MachInsts, but
340    // it will work better than a hard coded mask.
341    const Addr PCMask = ~(sizeof(MachInst) - 1);
342    req->setVirt(0, thread->readPC() & PCMask, sizeof(MachInst), 0,
343            thread->readPC());
344
345    Fault fault = thread->translateInstReq(req);
346
347    return fault;
348}
349
350
351void
352BaseSimpleCPU::preExecute()
353{
354    // maintain $r0 semantics
355    thread->setIntReg(ZeroReg, 0);
356#if THE_ISA == ALPHA_ISA
357    thread->setFloatReg(ZeroReg, 0.0);
358#endif // ALPHA_ISA
359
360    // keep an instruction count
361    numInst++;
362    numInsts++;
363
364    thread->funcExeInst++;
365
366    // check for instruction-count-based events
367    comInstEventQueue[0]->serviceEvents(numInst);
368
369    // decode the instruction
370    inst = gtoh(inst);
371    //If we're not in the middle of a macro instruction
372    if (!curMacroStaticInst) {
373        StaticInstPtr instPtr = NULL;
374
375        //Predecode, ie bundle up an ExtMachInst
376        //This should go away once the constructor can be set up properly
377        predecoder.setTC(thread->getTC());
378        //If more fetch data is needed, pass it in.
379        if(predecoder.needMoreBytes())
380            predecoder.moreBytes(thread->readPC(), 0, inst);
381        else
382            predecoder.process();
383        //If an instruction is ready, decode it
384        if (predecoder.extMachInstReady())
385            instPtr = StaticInst::decode(predecoder.getExtMachInst());
386
387        //If we decoded an instruction and it's microcoded, start pulling
388        //out micro ops
389        if (instPtr && instPtr->isMacroOp()) {
390            curMacroStaticInst = instPtr;
391            curStaticInst = curMacroStaticInst->
392                fetchMicroOp(thread->readMicroPC());
393        } else {
394            curStaticInst = instPtr;
395        }
396    } else {
397        //Read the next micro op from the macro op
398        curStaticInst = curMacroStaticInst->
399            fetchMicroOp(thread->readMicroPC());
400    }
401
402    //If we decoded an instruction this "tick", record information about it.
403    if(curStaticInst)
404    {
405        traceData = Trace::getInstRecord(curTick, tc, curStaticInst,
406                                         thread->readPC());
407
408        DPRINTF(Decode,"Decode: Decoded %s instruction: 0x%x\n",
409                curStaticInst->getName(), curStaticInst->machInst);
410
411#if FULL_SYSTEM
412        thread->setInst(inst);
413#endif // FULL_SYSTEM
414    }
415}
416
417void
418BaseSimpleCPU::postExecute()
419{
420#if FULL_SYSTEM
421    if (thread->profile) {
422        bool usermode = TheISA::inUserMode(tc);
423        thread->profilePC = usermode ? 1 : thread->readPC();
424        StaticInstPtr si(inst);
425        ProfileNode *node = thread->profile->consume(tc, si);
426        if (node)
427            thread->profileNode = node;
428    }
429#endif
430
431    if (curStaticInst->isMemRef()) {
432        numMemRefs++;
433    }
434
435    if (curStaticInst->isLoad()) {
436        ++numLoad;
437        comLoadEventQueue[0]->serviceEvents(numLoad);
438    }
439
440    traceFunctions(thread->readPC());
441
442    if (traceData) {
443        traceData->dump();
444        delete traceData;
445        traceData = NULL;
446    }
447}
448
449
450void
451BaseSimpleCPU::advancePC(Fault fault)
452{
453    if (fault != NoFault) {
454        curMacroStaticInst = StaticInst::nullStaticInstPtr;
455        fault->invoke(tc);
456        thread->setMicroPC(0);
457        thread->setNextMicroPC(1);
458    } else if (predecoder.needMoreBytes()) {
459        //If we're at the last micro op for this instruction
460        if (curStaticInst && curStaticInst->isLastMicroOp()) {
461            //We should be working with a macro op
462            assert(curMacroStaticInst);
463            //Close out this macro op, and clean up the
464            //microcode state
465            curMacroStaticInst = StaticInst::nullStaticInstPtr;
466            thread->setMicroPC(0);
467            thread->setNextMicroPC(1);
468        }
469        //If we're still in a macro op
470        if (curMacroStaticInst) {
471            //Advance the micro pc
472            thread->setMicroPC(thread->readNextMicroPC());
473            //Advance the "next" micro pc. Note that there are no delay
474            //slots, and micro ops are "word" addressed.
475            thread->setNextMicroPC(thread->readNextMicroPC() + 1);
476        } else {
477            // go to the next instruction
478            thread->setPC(thread->readNextPC());
479            thread->setNextPC(thread->readNextNPC());
480            thread->setNextNPC(thread->readNextNPC() + sizeof(MachInst));
481            assert(thread->readNextPC() != thread->readNextNPC());
482        }
483    }
484
485#if FULL_SYSTEM
486    Addr oldpc;
487    do {
488        oldpc = thread->readPC();
489        system->pcEventQueue.service(tc);
490    } while (oldpc != thread->readPC());
491#endif
492}
493
494